JP5918593B2 - Fuel cell system - Google Patents

Description

  The present invention relates to a fuel cell system that generates power using fuel gas and oxidant gas.

  Conventionally, a fuel cell system that generates power by supplying a fuel gas and an oxygen-containing gas to a fuel cell stack has been proposed. In such a fuel cell system, the main component of hydrogen is generated from raw fuels such as city gas and LPG. A reformer for generating fuel gas is provided inside.

  In order to generate fuel gas from this reformer, it is necessary to raise the reformer to the operating temperature. Therefore, when the fuel cell system is started, the raw fuel is burned to heat the reformer. However, in addition to the fact that the raw fuel contains carbon, the temperature of the device itself is low when the fuel cell system is started up, so that the flame is cooled and incomplete combustion occurs and carbon monoxide is likely to be generated. Become. Therefore, a large amount of carbon monoxide is contained in the exhaust gas discharged when the fuel cell system is started.

  Further, when the reformer starts generating fuel gas and the power generation operation is performed, the fuel gas that has not been used for power generation is now included in the exhaust gas as unburned gas.

  In Patent Document 1, a purification catalyst is provided as an exhaust gas purification device in an exhaust path of a fuel cell system in order to purify environmental impact components contained in the exhaust gas of the fuel cell system and safely discharge them outside the fuel cell system. The exhaust gas that has passed through the purification catalyst is discharged outside the apparatus.

  Further, since the purification action of this purification catalyst is activated when it reaches a certain temperature, in Patent Document 2, a heater is provided in the exhaust gas purification device and the temperature is raised in advance to a temperature at which the purification catalyst can treat the exhaust gas. The exhaust gas is purified by operating an ignition device for burning excess fuel gas that has not been used in the raw fuel supply means, the oxygen-containing gas supply means, and the fuel cells.

JP 2010-238446 A JP 2010-192272 A

  By the way, the conventional exhaust gas purification apparatus employs a method such as attaching the heater to the surface of the exhaust gas treatment apparatus in which the purification catalyst is accommodated or embedding it in the purification catalyst. However, there is a problem that the temperature does not rise sufficiently at the part away from the heater. Since the catalyst that does not reach the activation temperature cannot sufficiently exert the purification action, the purification catalyst housed in the purification catalyst case cannot be used effectively. On the other hand, it takes a long time to raise the temperature of the entire purification catalyst to the activation temperature. Therefore, if the output of the heater is increased in order to raise the temperature of the entire purification catalyst to the activation temperature in a short time, the purification catalyst in the vicinity of the heater is exposed to a high temperature, causing a problem in durability of the purification catalyst. In order to solve this problem, it is necessary to use a purification catalyst having excellent temperature durability, which leads to an increase in the cost of the fuel cell system.

  The present invention is for solving the above-described problems, and suppresses variations in the temperature of the purification catalyst during heating of the purification catalyst, and may contain unburned components such as carbon monoxide and hydrogen. An object of the present invention is to provide a fuel cell system capable of efficiently purifying exhaust gas from the system.

The present invention provides a fuel cell module for generating power, an exhaust gas passage for circulating exhaust gas discharged from the fuel cell module, a heater provided in the exhaust gas passage or downstream of the exhaust gas passage, and the exhaust gas flow A purification catalyst for purifying exhaust gas discharged from the fuel cell module, and a purification catalyst case in which the purification catalyst is housed, and a flow direction of the exhaust gas introduced into the purification catalyst case The heater is disposed at a position upstream of the purification catalyst and not in contact with the purification catalyst, and the heater further includes a non-heat generation portion formed integrally with the heat generation portion, the heater provided so as to at least partly buried in the purification catalyst, introducing the exhaust gas to the heating unit, the purification catalyst temperature rise of the heated exhaust gas Is a fuel cell system characterized Rukoto.

Further, the non-heat generating portion may pass through the downstream bottom portion of the purification catalyst case in the flow direction of the exhaust gas introduced into the purification catalyst case.

The exhaust gas purification apparatus may be configured to include the purification catalyst, the purification catalyst case, and the heater.

Further, the heat generating part may be provided so that at least a part of the heat generating part intersects a flow direction of exhaust gas introduced into the purification catalyst case. The term “intersection” as used herein means that the flow direction of the exhaust gas introduced into the exhaust gas raising / lowering device and the extending direction of the heat generating portion are not parallel. It may be a linear intersection or a curved intersection with respect to the flow direction of the exhaust gas.

Further, the heat generating part may be spiral.

Further, the spiral axis of the heat generating part may be provided so as to intersect with the flow direction of the exhaust gas introduced into the purification catalyst case.

  The heater may be a sheathed heater having a watt density of the heating unit of 4 W / cm 2 or less.

  With the configuration as described above, the purification catalyst is heated by the exhaust gas that has become high temperature when passing through the heat generating portion, so that variations in the temperature of the purification catalyst during heating of the purification catalyst can be suppressed, and purification can be performed. The utilization efficiency of the catalyst can be improved. Furthermore, since it is not necessary to increase the output of the heat generating portion excessively, the power consumption of the heater can be suppressed, local overheating of the purification catalyst is suppressed, and it is not necessary to obtain excessively high heat resistance for the purification catalyst. .

It is a block diagram of the fuel cell system of the present invention. It is a schematic block diagram of the fuel cell module of this invention. FIG. 3A is a partial cross-sectional view of the fuel cell system according to the first embodiment of the present invention. FIG. 3B is a partial top view of the fuel cell system according to the first embodiment of the present invention. FIG. 4A is a partial cross-sectional view of the fuel cell system according to the second embodiment of the present invention. FIG. 4B is a partial top view of the fuel cell system according to the second embodiment of the present invention. It is a fragmentary sectional view in a 3rd embodiment of a fuel cell system concerning the present invention. It is an external appearance perspective view in 3rd Embodiment of the fuel cell system which concerns on this invention. FIG. 7A is a partial cross-sectional view of the fourth embodiment of the fuel cell system according to the present invention. FIG. 7B is a partial top view of the fuel cell system according to the fourth embodiment of the present invention. FIG. 8A is a partial cross-sectional view of the fifth embodiment of the fuel cell system according to the present invention. FIG. 8B is a partial top view of the fifth embodiment of the fuel cell system according to the present invention. It is a graph showing the relationship between the watt density and the surface temperature of the sheathed heater.

  An embodiment of the present invention will be described below with reference to the drawings.

  FIG. 1 shows a schematic diagram of a fuel cell system 1. The fuel cell system 1 includes a fuel cell module 2 that generates power, an exhaust gas purification device 3 that removes and purifies unburned components such as carbon monoxide, hydrogen, and methane contained in the exhaust gas discharged from the fuel cell module 2, A heat recovery device 4 that recovers heat from the exhaust gas that has passed through the exhaust gas purification device 3 using a heat medium, a heat medium circulation path 30, and a heat storage tank 31 that stores heat recovered by the heat recovery device 4 are provided. For example, water can be used as the heat medium. In this case, the water heated in the heat recovery device 4 can be stored in the heat storage tank 31 as hot water.

  FIG. 2 shows a schematic diagram of the fuel cell module 2. The fuel cell module 2 includes a reformer 5 that generates a fuel gas using hydrogen-containing fuel, a hydrogen-containing fuel supply path 16 that supplies the reformer 5 with hydrogen-containing fuel as a raw fuel, an exhaust gas path 12, The oxidant gas flow path 13, the reformed water supply path 17 that supplies reformed water to the reformer 5, the cell stack 6 that generates power using the fuel gas and the oxidant gas, and the cell stack 6 are housed. And a housing 8 to be operated. In addition, FIG. 2 shows an outline and the structure and shape of each component are not limited to this. For example, the shape of the cells constituting the cell stack 6 may be a plate shape or a cylindrical shape. The cell stack may have a shape in which a plurality of cells are connected in series, parallel, or series-parallel.

  The reformer 5 is configured by filling a reforming catalyst therein, and can generate hydrogen by a steam reforming method, a partial oxidation method, an autothermal reforming method, or a combination thereof. it can.

  As the hydrogen-containing fuel, for example, a hydrocarbon fuel can be used. As the hydrocarbon fuel, a compound containing carbon and hydrogen in the molecule (may contain other elements such as oxygen) or a mixture thereof is used. Examples of the hydrocarbon fuel include hydrocarbons, alcohols, ethers, and biofuels. As these hydrocarbon fuels, those derived from conventional fossil fuels such as petroleum and coal, those derived from synthetic fuels such as synthesis gas, and those derived from biomass can be appropriately used. Specific examples of hydrocarbons include methane, ethane, propane, butane, natural gas, LPG (liquefied petroleum gas), city gas, town gas, naphtha, kerosene, and light oil. Examples of alcohols include methanol and ethanol. Examples of ethers include dimethyl ether. Examples of biofuels include biogas, bioethanol, biodiesel, and biojet.

  As the oxidizing agent, for example, air, pure oxygen gas (which may contain impurities that are difficult to remove by a normal removal method), or oxygen-enriched air can be used.

  A fuel gas supply path 9 is provided between the reformer 5 and the cell stack 6, and the fuel gas generated in the reformer 5 passes through the fuel gas supply path 9 from the lower part of the cell stack 6. Supplied to the cell. In the upper part of the cell stack 6, a combustion part 10 is formed in which the fuel gas and the oxidant gas that have not reacted in the cell stack 6 are joined and burned, and the reformer 5 is heated by the combustion in the combustion part 10. And combustion gas is generated.

  The housing 8 is a box having an internal space for housing the reformer 5 and the cell stack 6. The casing 8 includes a storage chamber 11 for storing the cell stack 6, an exhaust gas flow path 12 for allowing at least one of a fuel gas or an oxidant that has not reacted in the cell stack 6 or a combustion gas thereof to pass through as an exhaust gas. And an oxidant gas flow path 13 through which an oxidant gas introduced from the outside passes.

FIG. 3 shows a first embodiment in which the mesh-shaped heat generating portion 22 a is arranged so as to intersect the flow direction of the exhaust gas flowing through the purification catalyst case 21. FIG. 3A shows a partial cross-sectional view of the fuel cell system in the first embodiment. FIG. 3B shows a partial top view when the fuel cell system according to the first embodiment is viewed from the upstream side in the flow direction of the exhaust gas.
A heater 22 is provided inside an exhaust pipe 15 that is a part of the exhaust gas flow path 12 of the fuel cell module 2. Downstream of the exhaust pipe 15, a purification catalyst case 21 is provided that houses a purification catalyst 20 that purifies the exhaust gas by removing unburned components such as carbon monoxide, hydrogen, and methane from the exhaust gas.

As the purification catalyst 20, a generally known catalyst such as a noble metal catalyst such as platinum or palladium or a base metal catalyst such as manganese or iron can be used. These purify the unburned components such as carbon monoxide, hydrogen, methane and the like contained in the exhaust gas, and can be activated and efficiently purified by being heated. Further, the shape of the purification catalyst 20 is not particularly limited, and various shapes such as a honeycomb type, a pellet type, and a metal foam can be used as long as they can be accommodated in the purification catalyst case 21. Therefore, the fuel cell system 1 What is necessary is just to select suitably in the case of design of this.

  The catalyst temperature detector 23 is disposed on the bottom plate 24 that is the outer surface of the purification catalyst case 21. From the temperature change of the outer surface of the bottom plate 24, the temperature of the purification catalyst 20 accommodated in the purification catalyst case 21 can be estimated. Further, by arranging the purification catalyst case 21 on the outer surface, the maintenance becomes easy.

  Further, the bottom plate 24 includes a purified exhaust gas passage 25 for supplying the purified exhaust gas to the heat recovery device 4, and the purified exhaust gas flows into the heat recovery device 4 through the purified exhaust gas passage 25.

  The heat generating portion 22a is provided at a position upstream of the purification catalyst 20 and not in contact with the purification catalyst 20 in the flow direction of the exhaust gas. According to this, the exhaust gas discharged from the fuel cell module 2 passes through the heat generating part 22a and becomes high temperature, and then passes through the purification catalyst 20 to heat the purification catalyst 20 to the activation temperature. In other words, local overheating of the purification catalyst 20 due to the purification catalyst 20 coming into direct contact with the heat generating portion 22a can be suppressed, and consequently, the lifetime reduction of the purification catalyst 20 can be suppressed. Moreover, since it is not necessary to require excessive heat resistance for the purification catalyst 20, an increase in the cost of the fuel cell system can be suppressed.

  Further, the heat generating portion 22a is disposed so as to intersect the flow direction of the exhaust gas flowing through the purification catalyst case 21. In other words, it arrange | positions so that a part of cross section of the exhaust pipe 15 may be interrupted | blocked. According to this, the probability that the exhaust gas flowing into the exhaust pipe 15 comes into contact with the heating unit 22a or the probability that the exhaust gas passes through the vicinity of the heat generating unit 22a and is heated can be increased. In addition, in this embodiment, although the heat generating part 22a used the planar mesh-shaped heat generating part 22a, the shape which does not prevent the inflow of waste gas remarkably is sufficient.

  FIG. 4 shows a form in which the heat generating portion 22a is bent in a plane and arranged so as to intersect the flow direction of the exhaust gas. FIG. 4A shows a partial cross-sectional view of the fuel cell system in the second embodiment. FIG. 4B is a partial top view when the fuel cell system according to the second embodiment is viewed from the upstream side in the flow direction of the exhaust gas. In the present embodiment, an exhaust gas purification device 3 including a purification catalyst 20, a purification catalyst case 21, and a heater 22 is provided. The exhaust gas purification device 3 is connected downstream of an exhaust pipe 15 that is a part of the exhaust gas flow path 12 of the fuel cell module 2.

  Thus, by assembling the functions necessary for purifying the exhaust gas, the ease of assembly and the ease of maintenance of the fuel cell system 1 can be improved. In the present embodiment, the heat generating portion 22a is bent in a plane, but a shape that does not significantly hinder the inflow of exhaust gas is sufficient. For example, a spiral heat generating portion 22a may be used.

  FIG. 5 shows a third embodiment in which the heat generating portion 22a is formed in a spiral shape and arranged so as to intersect the flow direction of the exhaust gas. FIG. 6 is a perspective view of FIG. The heat generating part 22a is formed in a spiral shape, and its spiral axis (spiral central axis) is provided so as to intersect the flow direction of the exhaust gas passing through the heat generating part 22a.

  According to this, a large heat generation area can be ensured with respect to the cross-sectional area of the exhaust gas circulation portion in the exhaust gas purification device 3. Further, the probability that the exhaust gas flowing into the exhaust gas purification device 3 contacts the heat generating part 22a when the spiral axis (the central axis of the spiral) of the heat generating part 22a intersects the flow direction of the exhaust gas passing through the heat generating part 22a. Can be increased. Thereby, the uneven heating of the exhaust gas can be reduced, and consequently the temperature variation of the purification catalyst 20 can be reduced. In addition, as shown in FIG. 7, the same effect can be acquired even if it arrange | positions the helical heat generating part 22a cyclically | annularly (4th Embodiment). Further, as shown in FIG. 8, a plurality of spiral heat generating portions 22a may be arranged (fifth embodiment).

  In addition, the heater 22 of the present embodiment further includes a non-heat generating portion 22b configured integrally with the heat generating portion 22a. The heat generating part 22a and the non-heat generating part 22b may be formed continuously, or may be configured by assembling the heat generating part 22a and the non-heat generating part 22b directly or indirectly. . The heater 22 holds at least a part of the non-heat generating portion 22b in the purification catalyst 20 in a state where the heat generation portion 22a is held at a position upstream of the purification catalyst 20 and not in contact with the purification catalyst 20, and the bottom plate 24 of the purification catalyst case 21 is buried. Protrudes from the outside.

The heater 22 may be a sheathed heater in which a nichrome wire is embedded in a metal heater pipe and magnesia, which is an insulating powder, is filled. It has a heat generating portion 22a in which the nichrome wire is embedded and a non-heat generating portion 22b in which the nichrome wire is not embedded, and a heater terminal 22c is provided at the end of the non-heat generating portion 22b.

  According to this, since the portion in contact with the purification catalyst 20 does not generate heat, local overheating of the purification catalyst 20 can be suppressed, and it is not necessary to request excessive heat resistance when selecting the purification catalyst 20. . In addition, the catalyst temperature detection part 23 of this embodiment is a bottom plate so that the temperature detection point of the catalyst temperature detection part 23 is buried in the purification catalyst 20 so that the temperature of the purification catalyst 20 can be detected more directly. 24, the components passing through the purification catalyst case 21 are concentrated on one surface in this way, thereby making the manufacturing process of the exhaust gas purification device 3 and the gas leakage inspection process more efficient. You can also. Even if the exhaust gas leaks from the insertion portion of the non-heat generating portion 22b formed on the bottom plate 24, the unburned components are sufficiently removed from the exhaust gas reaching the vicinity of the bottom plate 24 located on the most downstream side of the purification catalyst 20. Therefore, the possibility that unburned components leak out of the fuel cell system can be reduced.

  When a sheathed heater is used as the heater 22, a watt density of 4 W / cm 2 or less is used. The watt density is the electric power per unit area in the heat generating portion 22a, and the watt density is greatly related to the life of the heater 22. As the watt density increases, the surface temperature increases and the life of the heater 22 decreases.

  FIG. 9 is a graph showing the relationship between the watt density during no wind and the surface temperature of the sheathed heater. When the watt density is 4 W / cm 2, the heater surface temperature is approximately 580 degrees. In the present invention, since the fluid flows into the heater 22 if the fuel cell device 1 has started to operate, there is no wind, so the actual surface temperature is lower than the temperature shown in the graph.

  Further, the heat resistance temperature of the heater 22 is determined by the material of the heater pipe. Generally, in a heater that requires a high heat resistance temperature, stainless steel such as SUS316L or SUS321, or a nickel alloy is used as the material of the heater pipe. For example, since the heat resistant temperature of stainless steel is 700 to 800 degrees, when stainless steel is used for the heater pipe, the surface temperature of the heater 22 does not exceed the heat resistant temperature if the watt density is 4 W / cm 2. .

  That is, normally, when the heater 22 is energized, it is necessary to always detect the temperature and control the energization so that the surface temperature does not exceed the heat resistance temperature. However, if the watt density is 4 W / cm 2 or less, the heater 22 Even if energization continues, the surface temperature of the heater 22 does not exceed the heat resistance temperature, so that troublesome energization control becomes unnecessary, and the durability of the heater 22 can be improved.

  In this graph, even when the watt density is 6 W / cm 2, the surface temperature is 700 ° C. or lower, which is lower than the heat resistance temperature of stainless steel. Therefore, the upper limit of the watt density may be set to 6 W / cm 2 on the graph. It is. However, since the surface temperature of the heater 22 varies depending on conditions such as the flow velocity of the fluid passing through the heater 22 and the ambient temperature, the watt density is preferably 4 W / cm 2 or less in order to provide a margin for the heat-resistant temperature. is there.

  Next, the operation of the above-described fuel cell system 1 will be described.

  When the operation of the fuel cell system 1 is instructed, in order to activate the purification catalyst 20 of the exhaust gas purification device 3, energization to the heater 22 is started and the oxidant gas flow path 13 of the fuel cell module 2 is externally connected. From which oxidant gas is introduced. Here, air will be described as an example of the oxidizing agent. The air introduced into the oxidant gas flow path 13 is supplied to an oxidant electrode (not shown) of the cell stack 6. However, since the reforming operation is not yet performed in the reformer 5, the fuel gas mainly composed of hydrogen is not supplied to the fuel electrode (not shown) of the cell stack 6, and power generation by the cell stack 6 is performed. Absent. Therefore, the supplied air passes through the exhaust gas passage 12 as it is and flows into the exhaust gas purification device 3.

  The air flowing into the exhaust gas purification device 3 is heated by the heater 22 to become high-temperature air, and heats the purification catalyst 20 when passing through the purification catalyst case 21. Instead of heating the purification catalyst 20 in contact with the heating unit 22a, the purification catalyst 20 is heated by high-temperature air that is preheated by the heating unit 22a and passes through the purification catalyst case 21, so that the purification catalyst 20 is at a distance from the heating unit 22a. The variation in the temperature of the purification catalyst 20 caused by this is suppressed.

  While the high temperature air flows into the purification catalyst case 21, the temperature of the purification catalyst 20 is monitored by the catalyst temperature detection unit 23. After it is determined from the temperature detected by the catalyst temperature detection unit 23 that the temperature of the purification catalyst 20 has reached the activation temperature, the reforming is performed in order to generate the fuel gas necessary for the cell stack 6 to perform the power generation operation. Supply of raw fuel to the apparatus 5 is started.

  In order for the reformer 5 to generate fuel gas containing hydrogen as a main component from the raw fuel, the temperature of the reformer 5 needs to reach the operating temperature. The temperature of the device 5 is low and has not reached the operating temperature. Therefore, the raw fuel supplied to the reformer 5 is discharged from the reformer 5 without being sufficiently reformed. The unreformed fuel discharged from the reformer 5 is combusted in the combustion section 10 in the fuel cell module 2, and the reformer 5 is heated by this combustion, and the generated combustion gas is discharged into the exhaust gas flow path 12. Flow into.

  As described above, when the fuel cell system 1 is started, unreformed fuel is burned in the combustion unit 10 to form a flame. At this time, the casing 8 and the reformer 5 that still constitute the fuel cell module 2 are formed. Therefore, when the flame is in contact with those low temperature portions, the flame is cooled, incomplete combustion occurs, and carbon monoxide may be generated.

  Exhaust gas that may contain carbon monoxide flows into the exhaust gas flow path 12 and flows from the exhaust pipe 15 into the exhaust gas purification device 3 provided downstream thereof. In the exhaust gas purification device 3, since the purification catalyst 20 has already been heated and the entire catalyst is activated, the unburned components in the exhaust gas are purified by the purification catalyst 20, and the purified exhaust gas flows into the purified exhaust gas stream. It flows into the heat recovery apparatus 4 downstream through the path 25.

  While the exhaust gas is purified in this way, the reformer 5 is heated by combustion and the temperature rises. When the reforming device 5 reaches the operating temperature, raw fuel and water are supplied to the reforming device 5, and fuel gas containing hydrogen as a main component is generated. Then, the fuel gas and air are supplied to the cell stack 6 to perform a power generation operation.

  Specifically, the fuel gas is supplied to the fuel electrode (not shown) of each cell of the cell stack 6 through the fuel gas supply path 9. Air is introduced from the outside, flows into the oxidant gas flow path 13, and is supplied to the oxidant electrode (not shown) of each cell. The fuel gas and air that have not been used for the reaction in the cell stack 6 are used for combustion in the combustion unit 10 to generate combustion gas. Although the combustion gas may contain unburned gas, unburned components in the combustion gas are purified by the purification catalyst 20, and the purified exhaust gas passes through the purified exhaust gas flow path 25 to recover heat downstream. It flows into the device 4.

  Since the exhaust gas flowing through the exhaust gas flow path 12 at the time of power generation operation is high temperature and the purification catalyst 20 has already reached a temperature to be activated, the purification catalyst 20 is activated even if the exhaust gas is not heated by the heater 22. Will be able to keep. Therefore, the power supply to the heater 22 may be stopped during the power generation operation.

  In addition, when the temperature of the purification catalyst 20 detected by the catalyst temperature detection unit 23 during the power generation operation becomes a predetermined value or less, the energization of the heater 22 may be started again. The predetermined value here may be a temperature lower than the activation temperature lower limit value of the purification catalyst 20 or an arbitrary temperature higher than the activation temperature lower limit value of the purification catalyst 20. As in Patent Document 1, in an exhaust gas purification catalyst having a structure in which reformed water is heated (or vaporized) by heat generated by the purification catalyst, the purification catalyst temperature may be lowered even during normal operation. Further, since the structure removes heat from the purification catalyst case, the temperature variation of the purification catalyst tends to be further increased. However, by applying the present invention in which the high temperature exhaust gas is brought into contact with the purification catalyst, temperature variation in the purification catalyst case 21 is suppressed even during the power generation operation of the fuel cell device, and the purification action of the purification catalyst 20 is stabilized. Can be maintained.

  The illustrated embodiments are merely examples of the present invention, and the present invention includes various improvements and modifications made by those skilled in the art within the scope of the claims in addition to those directly illustrated by the described embodiments. Needless to say, it is included.

  For example, although various forms have been shown as the first to fifth embodiments, the shape of the heat generating portion 22a may be any shape that does not significantly disturb the inflow of exhaust gas. You may replace with the heat-emitting part 22a which concerns on other embodiment. Further, the plurality of heat generating portions 22 a may be arranged in layers with respect to the flow direction of the exhaust gas flowing through the purification catalyst case 21.

  For example, FIG. 4 shows an embodiment in which the catalyst temperature detection unit 23 is arranged on the outer surface of the purification catalyst case, and in FIGS. 5, 7 and 8, the catalyst temperature detection unit is buried in the purification catalyst 20. Although the embodiment in which 23 is arranged is shown, the present invention is not limited to this. The catalyst temperature detection unit 23 only needs to be able to indirectly estimate the purification catalyst temperature. Therefore, the catalyst temperature detection unit 23 may be disposed in any of the exhaust gas purification apparatuses 3 as long as a temperature change having a correlation with the temperature change of the purification catalyst occurs.

  3 shows an embodiment in which the heater 22 protrudes outward from the side wall of the purification catalyst case 21, but as shown in FIGS. 4 and 6, the heater 22 further includes a non-heat generating portion 22b, and the purification catalyst. The case 21 may protrude from the bottom plate 24.

  3 and FIG. 4, the exhaust gas purification device 3 is connected to the exhaust pipe 15 which is a part of the exhaust gas flow path 12, but the exhaust pipe 15 is omitted and the exhaust gas in the housing 8 is You may connect directly to the discharged | emitted part. Further, in the embodiment shown in FIG. 6, the purification catalyst case 21 is inserted into the exhaust pipe 15, but even if the purification catalyst case 21 is not inserted into the exhaust pipe 15 as in the embodiment shown in FIG. 3. Good. In any form, it is sufficient that the exhaust gas does not flow out from the connecting portion of each part.

2 Fuel Cell Module 3 Exhaust Gas Purification Device 20 Purification Catalyst 21 Purification Catalyst Case 22 Heater 22a Heating Part 22b Non-heating Part

Claims (7)

A fuel cell module for generating power; an exhaust gas channel for distributing exhaust gas discharged from the fuel cell module; a heater provided in the exhaust gas channel or downstream of the exhaust gas channel; and downstream of the exhaust gas channel A purification catalyst for purifying exhaust gas discharged from the fuel cell module; and a purification catalyst case in which the purification catalyst is housed, and the purification catalyst in a flow direction of the exhaust gas introduced into the purification catalyst case And the heater further includes a non-heat generating portion formed integrally with the heat generating portion, wherein at least a part of the non-heat generating portion is at least part of the non-heat generating portion. A fuel cell system comprising the heater so as to be buried in the purification catalyst .   2. The fuel cell system according to claim 1, wherein the non-heat generating portion penetrates a downstream bottom portion of the purification catalyst case in a flow direction of exhaust gas introduced into the purification catalyst case.   3. The fuel cell system according to claim 1, wherein an exhaust gas purification device is configured to include the purification catalyst, the purification catalyst case, and the heater.   The fuel cell system according to any one of claims 1 to 3, wherein at least a part of the heat generating portion intersects a flow direction of exhaust gas introduced into the purification catalyst case. .   The fuel cell system according to claim 4, wherein the heat generating portion has a spiral shape.   6. The fuel cell system according to claim 5, wherein the heat generating portion is provided so that a spiral axis intersects a flow direction of exhaust gas introduced into the purification catalyst case.   The fuel cell system according to any one of claims 1 to 6, wherein the heater is a sheathed heater having a watt density of the heating unit of 4 W / cm 2 or less.

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